The present invention relates generally to fluid operated steering apparatus, such as hydraulically operated steering apparatus used on ships, boats and the like (hereinafter, "water vessel"), and, more particularly, to a method of and apparatus for auxiliary control of fluid operated steering apparatus to enable control of the steering apparatus in the event the main steering control system becomes defective or completely inoperable.
The recent trend in constructing ocean-going cargo ships has been towards more complex and greater tonnage vessels capable of transporting large quantities of potentially dangerous cargo, such as crude oil or liquified natural gas, etc. Although the chances of a serious mishap are slight when the vessel is on the open seas, the possibility of such occurrence is greatly increased when the vessel is in shallow waters or in harbors or other congested areas. Under these circumstances, one of the greatest causes of serious accidents has been the loss in steering capability, resulting in collisions with nearby vessels, docks or other obstructions.
In general, the steering apparatus in such water vessels are hydraulically operated and the steering control systems therefor include a somewhat complex combination of mechanical, hydraulic and electrical devices, such as disclosed in U.S. Pat. Nos. 2,892,310 and 3,468,126, both issued to Mercier. Although the hydraulic steering control systems provide satisfactory operation under normal conditions, the component devices are all susceptible to failure and the entire steering control system can be rendered inoperable. These steering control systems provide no reliable and conveniently operable means for enabling control of the steering apparatus when the main steering control system is rendered inoperable. Rather, they merely include manual control devices which permit limited control of the steering mechanism.
While manually operable devices may permit some steering control of the vessel, several drawbacks are evident. For example, since the manually operable devices are usually located in the steering gear room or other areas physically separated from the bridge, the steering commands issued by those in the bridge, who can observe the vessel's heading and its surroundings, can be misunderstood or too slowly carried out by those operating the manual control devices. Thus, the vessel can be inadvertently mis-directed into an accident.
Another proposal for providing auxiliary steering control involves at least partially duplicating the devices of the steering control system. Although redundancy of hardware may offer satisfactory operation in certain situations, it would be unduly expensive, space consuming and not necessarily fool-proof. For example, if the vessel's electrical system failed, all electrically operated components in both the existing and the redundant steering control systems would be inoperable, thereby rendering the redundant system ineffective.
Accordingly, it is an object of the present invention to provide new and improved method of and apparatus for auxiliary control of fluid-operated steering apparatus in water vessels. It is also an object of the present invention to provide a new and improved auxiliary control system for fluid-operated steering apparatus, and a method of carrying out same, which is available for essentially immediate utilization when the main steering control system is rendered defective or completely inoperable.
In addition, it is an object of the invention to provide a new and improved method of and apparatus for auxiliary control of fluid-operated steering apparatus in water vessels, which can be initiated directly from the same location where the main steering control system is operated.
Another object of the invention is to provide a new and improved method of and apparatus for auxiliary control of fluid-operated steering apparatus in water vessels, which can be conveniently incorporated into virtually any type of conventional fluid-operated steering apparatus.
It is an additional object of the present invention to provide a new and improved method of and apparatus for auxiliary control of fluid-operated steering apparatus in water vessels, which can be implemented by means independent of the main power source or any other power source for the main steering control system.
It is yet another object of the present invention to provide a new and improved method of and apparatus for auxiliary control of fluid-operated steering mechanisms in water vessels, which can provide at least limited control of the steering mechanism without requiring any electrical power.
It is a further object of the present invention to provide a new and improved method of and apparatus for auxiliary control of fluid-operated steering mechanisms in water vessels, which is completely independent of the main steering control system.
Objects and advantages of the invention are set forth in part above and in part below. In addition, these and other objects and advantages of the invention will become apparent herefrom, or may be appreciated by practice with the invention, the same being realized and attained by means of the instrumentalities, combinations and methods pointed out in the appended claims. Accordingly, the present invention resides in the novel parts, constructions, arrangements, improvements, methods and steps herein shown and described.